Year	Annual Number
1970	0
1971	150000
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	40000
1980	0
1981	0
1982	0
1983	600000
1984	0
1985	0
1986	0
1987	0
1988	0
1989	0
1990	0
1991	2700000
1992	0
1993	0
1994	1200000
1995	0
1996	1600000
1997	0
1998	0
1999	23000000
2000	0
2001	0
2002	0
2003	0
2004	2300000
2005	3500000
2006	0
2007	0
2008	1400000